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101.
A combined in vivo/in vitro model of galactosamine hepatotoxicity was employed to test whether previously reported cytoprotective actions of cystamine administration on galactosamine-induced hepatic injury in vivo could be attributed to a direct action of cystamine on toxicant-challenged hepatocytes. In this model, male Sprague-Dawley rats received a 400 mg/kg galactosamine challenge via intraperitoneal injection 1 hr prior to portal vein cannulation for hepatocyte isolation. Isolated cells are established in monolayer culture and galactosamine-induced cellular injury is then expressed over the ensuing 24-48 hr in culture. Consistent with the biochemical basis of galactosamine-induced hepatocellular injury in vivo, cytotoxicity could be prevented by in vitro uridine treatments within 3 hr of the in vivo galactosamine challenge, but not when added 12 hr later. Cystamine, in contrast, exhibited a cytoprotective effect even when added to cultures 12 hr after the in vivo toxicant challenge. Post-toxicant cytoprotection by cystamine in vitro was concentration dependent and did not produce an alteration of hepatocyte nonprotein sulfhydryl content. Post-toxicant cytoprotection by uridine and cystamine in this in vivo/in vitro model of toxicity were fully consistent with in vivo protection from galactosamine-induced necrosis by these agents. This model eliminates potential "extrahepatic" mechanisms for cystamine's hepatoprotective effect and demonstrates a direct cytoprotective action on galactosamine-challenged hepatocytes.  相似文献   
102.
This study was designed to: (a) assess the degree to which rehabilitation staff rate the severity of maladaptive behaviors on Part II of the AAMD Adaptive Behavior Scale (ABS) and, on the basis of the obtained rating, (b) develop a socially validated revision of the scoring system to allow more accurate classification of mentally retarded individuals as having mild, moderate, or severe behavior problems. On the basis of the modal ratings obtained from various service agencies for "occasionally" and "frequently" on Part II of the ABS, we constructed a revised scoring system. Preliminary use of the scoring system suggests satisfactory agreement between "severity profile" scores and subjective ratings of individuals classified by service agencies as demonstrating mild, moderate, or severe behavior problems.  相似文献   
103.
We aimed to report the implementation of a phenylketonuria (PKU) transition program and study the effects of follow-up with an adult team on metabolic control, adherence, and loss of follow-up. Fifty-five PKU patients were analysed in the study periods (SP): 2 years before (SP1) and after the beginning of adult care (SP2). Retrospective data on metabolic control and number of clinic appointments were collected for each SP, and protein intakes were analysed. In SP2, three patients (6%) were lost to follow-up. There was a small but statistically significant increase in median number of annual blood spots from SP1 to SP2: 11 (7–15) vs. 14 (7–20); p = 0.002. Mean ± SD of median blood Phe remained stable (525 ± 248 µmol/L vs. 552 ± 225 µmol/L; p = 0.100); median % of blood Phe < 480 µmol/L decreased (51 (4–96)% vs. 37 (5–85)%; p = 0.041) and median number of clinic appointments increased from SP1 to SP2: (5 (4–6) vs. 11 (8–13); p < 0.001). No significant differences were found regarding any parameter of protein intake. Our results suggest that the implementation of an adult service was successful as impact on metabolic control was limited and attendance remained high. Continuous dietetic care likely contributed to these results by keeping patients in follow-up and committed to treatment.  相似文献   
104.
In patients with phenylketonuria (PKU), treated by diet therapy only, evidence suggests that areal bone mineral density (BMDa) is within the normal clinical reference range but is below the population norm. Aims: To study longitudinal bone density, mass, and geometry over 36 months in children with PKU taking either amino acid (L-AA) or casein glycomacropeptide substitutes (CGMP-AA) as their main protein source. Methodology: A total of 48 subjects completed the study, 19 subjects in the L-AA group (median age 11.1, range 5–16 years) and 29 subjects in the CGMP-AA group (median age 8.3, range 5–16 years). The CGMP-AA was further divided into two groups, CGMP100 (median age 9.2, range 5–16 years) (n = 13), children taking CGMP-AA only and CGMP50 (median age 7.3, range 5–15 years) (n = 16), children taking a combination of CGMP-AA and L-AA. Dual X-ray absorptiometry (DXA) was measured at enrolment and 36 months, peripheral quantitative computer tomography (pQCT) at 36 months only, and serum blood and urine bone turnover markers (BTM) and blood bone biochemistry at enrolment, 6, 12, and 36 months. Results: No statistically significant differences were found between the three groups for DXA outcome parameters, i.e., BMDa (L2–L4 BMDa g/cm2), bone mineral apparent density (L2–L4 BMAD g/cm3) and total body less head BMDa (TBLH g/cm2). All blood biochemistry markers were within the reference ranges, and BTM showed active bone turnover with a trend for BTM to decrease with increasing age. Conclusions: Bone density was clinically normal, although the median z scores were below the population mean. BTM showed active bone turnover and blood biochemistry was within the reference ranges. There appeared to be no advantage to bone density, mass, or geometry from taking a macropeptide-based protein substitute as compared with L-AAs.  相似文献   
105.
106.
BackgroundDexamethasone has been shown to reduce postoperative pain and opioid consumption for total joint arthroplasty patients; however, its impact on patients who received neuraxial anesthesia (NA) is not well described. We examined the impact of perioperative dexamethasone on outcomes for patients undergoing direct anterior approach total hip arthroplasty (THA) under NA.MethodsA retrospective review was conducted for 376 THA patients from a single institution. Univariate analysis was used to compare postoperative outcomes for 164 THA patients receiving dexamethasone compared to 212 who did not receive dexamethasone.ResultsNo differences in age, gender, body mass index, or American Society of Anesthesiologists (ASA) Score were observed between the groups. Patients receiving perioperative dexamethasone reported statistically significantly lower postanesthesia care unit (PACU) pain numeric rating scale (Dexamethasone 1.6 vs No dexamethasone 2.3, P = .014) and received lower PACU morphine milligram equivalents (MME) (Dexamethasone 8.57 vs No dexamethasone 11.44, P < .001). Patients receiving dexamethasone had significantly shorter LOS (Dexamethasone 29.40 vs No dexamethasone 35.26 hrs., P < .001).ConclusionPerioperative dexamethasone is associated with decreased postoperative pain and narcotic consumption, and shorter length of stay for patients undergoing primary direct anterior approach THA with NA.  相似文献   
107.
BackgroundApproximately 20% of patients are dissatisfied with their total knee arthroplasty (TKA) at 1-year post-surgery. Met expectations have been found by some to significantly predict satisfaction. The role of met expectations in determining patient satisfaction has not been exhaustively explored. The primary aim of this study is to evaluate if met expectations moderate the relationship between pain and function variables and satisfaction.MethodsPatients who underwent primary TKA for osteoarthritis were included in the study (n = 304). Patient-reported outcomes at pre-surgery and 1-year post-surgery were collected. The Knee Society Score (KSS) satisfaction subscale was used as the dependent variable. Candidate independent variables included the following: demographics, KSS, Knee injury and Osteoarthritis Outcome Score (KOOS), 12-Item Short Form Health Survey (SF-12), Hospital Anxiety and Depression Scale, Pain Catastrophizing Scale, Self-Administered Comorbidity Questionnaire, and University of California Los Angeles activity score. Separate linear regression models were created to test interactions for KSS met expectations with pain and KSS met expectations with function.ResultsSignificant predictors of satisfaction were KSS symptoms (pain), KOOS activities of daily living (function), KSS met expectations, KOOS pre-surgery activities of daily living, body mass index, and SF-12 general health. A significant interaction between met expectations and pain was found (P = .043) and the met expectations and function interaction approached significance (P = .086). For both interactions, as met expectations increased, pain and function predicted satisfaction less strongly.ConclusionMet expectations were found to moderate the relationship between pain and satisfaction. There may be more value in improving pain for patients with low met expectations.Level of evidenceLevel IV.  相似文献   
108.
Background/purposeAdolescents have poor outcomes following testicular torsion directly attributable to delay from onset of symptoms to presentation to hospital. The aim of this study was to investigate the barriers to urgent presentation in young men.MethodsSemistructured interviews were undertaken with young men (11–19 years), using a topic guide exploring issues surrounding testicular pain and health. Thematic analysis was undertaken using a framework approach.ResultsTwenty-seven adolescents were recruited, data saturation was reached at sixteen participants, and median age was 13.5 years (range 11–18). The process by which an adolescent gets to hospital with testicular pain is slow. They must recognize the problem and alert their parents, who then use a ‘watch and wait’ policy to assess need for medical review, often leaving it ‘a day’ or overnight. Adolescent males do not engage with healthcare services independently of their parents. Additional factors preventing early presentation include: absence of knowledge about testicular pathology from adolescents and their parents; concern from the young people about raising a false alarm and family concerns about burdening healthcare services.ConclusionsRecommendations include designing a testicular health education campaign for young men and educating parents regarding the medical conditions where a ‘watch and wait’ policy may be harmful to their child.Level of evidenceVI  相似文献   
109.
Epilepsy and the GABA-hypothesis a brief review and some examples   总被引:9,自引:0,他引:9  
A brief review is given with regard to the GABAergic alterations in experimental and genetic models of epilepsy and human epilepsy, illustrating, among others, that agents exist, both convulsants and anticonvulsants, that are capable of interacting with GABA's synthesis, storage, extraneuronal release, presynaptic reuptake, postsynaptic destruction and activation. The so-called "GABA-hypothesis" of epilepsy implies that a reduction of GABA-ergic inhibition results in epilepsy while an enhancement of GABAergic inhibition results in an antiepileptic effect. The examples presented, in support of the "GABA-hypothesis", concern the effects of some exogenous [pentylenetetrazol (PTZ) and methyl 6,7-dimethoxy-4-ethyl-beta-carboline-3-carboxylate (DMCM)] and some endogenous convulsants on the postsynaptic GABAA receptor. The studied endogenous convulsants were the guanidino compounds which are known to increase in uremia and hyperargininemia. PTZ and DMCM dose-dependently reduced GABA responses on mouse neurons in cell culture. The benzodiazepine receptor antagonist CGS 9896 antagonized the DMCM- but not the PTZ-induced inhibition of GABA-responses. The guanidino compounds guanidine, methylguanidine, creatinine, guanidinosuccinic acid (increased in uremia) and arginine, homoarginine, alpha-keto-delta-guanidinovaleric acid and argininic acid (increased in hyperargininemia) decreased both GABA- and GLY-responses. The guanidino compounds were equally potent in decreasing GABA- and GLY-responses and CGS 9896 did not antagonize the guanidino compound-induced inhibition of GABA responses. The presented results indicate that the studied convulsants inhibit GABAergic inhibition through interaction with distinct sites at the postsynaptic GABAA receptor. The demonstrated effect might, in agreement with the "GABA-hypothesis", underlie the epileptogenicity of these compounds in animal models and might have pathophysiological importance in uremia and hyperargininemia.  相似文献   
110.
Pager-based activity sampling (PAS) is described as a cost-effective and unobtrusive method for sampling residents' activities in clinical settings. A sample program evaluation is presented using residents in an urban children's hospital resident-training program. The purposes of the program evaluation were: (a) to establish a behavioral baseline that would help clinical faculty understand how residents were using their time, and (b) to determine whether alterations in the way residents were assigned within the hospital resulted in desired changes to time spent. The primary rationale for changing resident-assignment policies were: (a) to decrease the time residents were spending in transit between various locations within the hospital, and (b) to increase the time spent by residents in educational activities and in direct contact with patients and their families. This PAS application demonstrates that the technique can produce statistically supportable conclusions, at minimal cost, without unduly disrupting either the residents or their patients. PAS is compared with other time-sampling methods, its limitations are discussed, and suggestions for future applications are provided.  相似文献   
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